A gas diffuser case for use in collecting compressed gas ejected from a centrifugal compressor generally comprises a plurality of internal channels known as diffuser passages. Each channel has an inlet axis which is somewhat tangential to the compressor's rotational axis, and is thus oriented in a direction to receive the compressed gas ejected from the compressor.
In many applications, the acute angle which forms the edge between adjacent channel inlets requires a very small radius at its tip and a very smooth surface to provide optimal efficiency for the compressor-diffuser assembly. Providing such radius and surface, however, can be challenging and room for improvement exists.